1. Field of the Invention
The present invention relates to a method of reading out images and a related device and, more particularly, to a method of reading out digital images with a dynamic extendable frame.
2. Description of the Related Art
In today's technology, digital image capturing devices are extremely popular devices, and users are demanding increasingly better performance from digital image capturing devices. In general, when using the digital image capturing device, the processor sometimes requires a period of time to perform an operation (such as switching between modes). For both digital cameras and digital video cameras, the digital image sensor (such as a CCD) continuously downloads images. The sensor itself cannot extend the captured frame until the processor finishes the current operation or procedure.
In order to extend frames, one prior art technology utilizes a method of defining a V-blanking phase having a fixed period of time. However, since each V-blanking phase has a fixed period of time, it cannot be dynamically adjusted. When the image capturing device is switched between different modes, the processor requires a different processing time for the switching procedure. In order to make the V-blanking phase suitable for different conditions, the V-blanking phase needs to be defined as the maximum value of the different processing times for different conditions. Therefore, the V-blanking phase is always larger than the processing time under all conditions, which causes unnecessary delays for the user. If the V-blanking phase is shorter than the operational processing time of the processor, the data for the next frame may be missing, which can cause the digital image capturing device to crash.
In another prior art technology, the timing generator is turned off when the processor is operating, or the timing generator is switched into an idle phase until the image processing procedure has finished. When the timing generator is turned off, the photo diodes of the digital image capturing device still continuously accumulate dark current, which can lead to increasing noise in the frames.
Therefore, it is desirable to provide a method of reading out digital images with a dynamic extendable frame, which can also eliminate noise to mitigate and/or obviate the aforementioned problems.